Sql语句优化

in修改为exists

一：in

hql +=" and b.newsid  in (select f.object from FeedBack f where f.type=1 and f.operate=1 and f.userid in (select u.userid from SysUser u where f.userid = u.userid and u.username like '%"+filterValue+"%'))";

 

二：exist

hql +=" and exists (select f.object from FeedBack f where b.newsid = f.objectid and f.type=1 and f.operate=1 and exists (select u.userid from SysUser u where f.userid = u.userid and u.username like '%"+filterValue+"%'))";

第一个：select u.userid from SysUser u where f.userid = u.userid and u.username like '%"+filterValue+"%'；

第二个：select f.object from FeedBack f where b.newsid = f.objectid and f.type=1 and f.operate=1

第三个：select b from PreNewsTips  b where 1=1 ;

三：

hql += "select max(n.orders) from NewsIssueClassify n where parentid=?";